Problem of the identification of typewriter makes and models

In this paper, the author studies the generalities of the problem of a typewriting machine identification from a text. He outlines in detail the identification systems which are commercially available, the “Atlas der Schreibmaschinenschrift Pica” from Josef Haas (German) and the “System for Identification of Typewriter Makes Using the Card Index” distributed by the General Secretariat of I.C.P.O.—Interpol. He comments briefly on two well-known systems: that of G. de la Durantaye of Toronto, Canada, and that of D. A. Crown from Washington, D.C., U.S.A. Finally, the author proposes a working method and exposes the limits of the identification possibilities.